<select class="form-select">
    <option value="">-- 选择会员等级 --</option>
    {% for level in levels %}
    <option value="{{ level.id }}" {% if selected_id == level.id %}selected{% endif %}>
        {{ level.name }}{% if level.is_default %} (默认){% endif %}
    </option>
    {% endfor %}
</select> 